That's much easier to digest than the 17 pages of the previous thread!
The fact you have resigned before they have completed the process means you are unlikely to have a case for unfair dismissal, constructive dismissal or similar. It sounds like the process has been poor which may have given you a case but unfortunately it is too late now.
I am a little surprised the union is not representing you. Are you still a member? If you are, I would query this. It may also be worth checking your home insurance to see if that includes legal cover and, if so, whether they can help.
If you have taken more holiday than your entitlement normal practice would be to deduct the difference from your final pay.